Slate-pencil sharpener



(No Model.)

B. HAMBUJER.

SLATE PENGIL SHARIPBNER.

No. 406,900. Patented July 16, 1889.

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EPIIRAIM HAMBUJER, OF DETROIT, MICHIGAN.

SLATE-PENCIL SHARPEN ER.

SPECIFICATION forming part of Letters Patent No. 406,900, dated. July16, 1889.

Application filed May 9, 1889. Serial No. 310,159. (No model.)

To aZZ whom it may concern:

Be it known that I, EPHRAIM HAMBUJER, a citizen of the United States,residing at Detroit, in the county of -Wayne and State of Michigan, haveinvented certain new and useful Improvements in Slate-Pencil Sharpeners,of which the following is a specification, reference being had thereinto the accompanying drawings.

This invention relates to new and useful improvements in slate-pencilsharpeners; and the invention consists in the novel construction andarrangement of parts, all as more fully hereinafter described, and shownin the accompanying drawings, in which Figure 1 is a front elevation ofmyimproved slate-pencil sharpener. Fig. 2 is aside elevation thereof.Fig. 3 is an enlarged perspective view of the device slightly modified,and Fig. 4 are slate-pencils partly and fully sharpened.

A is a steel plate provided with the shank B, for securing it in asuitable handle C.

In the upper edge of the steel plateA is cut a V-shaped slot D, providedwith a circular enlargement E at the narrowest end, and the edges ofthis slot and enlargement are sharpened.

In any suitable part of the body of the plate A, I form one or moreapertures F,preferably by means of a pointed tool, which forms a burr Gon the reverse side of the plate, and this aperture or apertures Iscrew'thread interiorly. The aperture F is made of smaller diameter thanthe diameter of the slate-pencil, and if more apertures are providedthey are made of different sizes.

In practice a slate-pencil can be readily sharpened by first screwing itinto the aperture F, or where there are more into the largest one. Byrotating the pencil with the fingers this is easily accomplished and thepencil is thereby reduced in thickness for the length of the point. Thescrew-threads out upon it are then shaved off and a tapering pointformed by drawing the point of the pencil through the V-shaped slot D.The aperture E is adapted for cutting away the shoulder formed at thebase of the point of the pencil.

If the sharpener is provided with several screw-holes F, as shown inFig. 3, then the point of the pencil is formed by screwing the pencilsuccessively into the different holes, beginning with the largest andfinishing with the smallest, so that a point of the form shown at H inFig. 4 is formed, which is then quickly finished to a tapering point byusing the V- shaped slot, as before described.

My device is inexpensive, but will be found to be very serviceable, andit has the advantage that a slate-pencil, even of the softest kind ofslate, maybe sharpened without danger of breaking off the point.

\Vhat I claim as my invention is- 1. In a slate-pencil sharpener, theplate A, provided with the V-shaped slot D, having knife-edges and oneor more screw-thi eaded apertures, as F, substantially as described.

2. As a new article of manufacture, aslatepencil sharpener consisting ofthe steel plate A, secured to a handle and provided with the V-shapedslot D, the circular enlargem ent,and one or more screw-threadedapertures, substantially as described.

In testimony whereof I affix my signature, in presence of two witnesses,this 6th day of May, 1889.

EPIIRAIM IIAMBUJER.

Witnesses:

V. A. Ross, A. B. EATON.

